Electric-motor-starting device.



No.850,16 5. PATENTED APR.16, 1907. 1); R.'..KNAPP & H. E. GADE.

ELECTRIC MOTOR STARTING DEVICE. urmouxou mm mm; 7, 19oa.

Imawiora' UNITED STATES PATENT OFFICE.

DAVID R. KNAPP, OF PHILADELPHIA, AND HOWARD E. CADE,

PENOOYD, PENNSYLVANIA.

ELEOTRIC-MOTOHI-STAHTING DEVICE.

" To all whom it may concern.-

Be it known that we, DAVID R. KNAPP and Howmu E. CADE, citizens of the United States, residing, respectively, at Philadelhia, in the county of Philadelphia, and at Pencoyd, in the county of Montgomery, both in the State of Pennsylvania, have invented means for starting an electric motor after power has been supplied to the same through a: resistance and means for cutting out t c said resistance in steps as the motor increases in s eed; second, toprovide means to allow use e amountof current to flow to the motor upon starting from restin case the load on theimotorwould otherwise cause excessive current fl'ow with detrimental resultspthird, to provide automatic means for openingthe motor-circuit when the" motor is running in .case the load current became excessive enough to be detrimental, and automatic means for closing the'same and allowing only a desired amount of current to-flow to the.

' motor inorder to maintain its static torque,

and means rovided to allow the motor to start after t e loadflh'as been so reduced as not to cause an excessive amount of current- We attain these 0bcompanying drawing,in which- F1 are 1 1s a view showin diagrammaticall 3 t e connections and mec anism.

imilar letters refer to similar ,parts thi'gfaug'h the view.

A is the motor, which is desired tobe started and controlled.

., .f B, B, B; and B are-magnet-cores enerv ectively, by the windings C, C, and The windingsC, C, and 1C are assisted by their auxiliary windin s. D,

I D", and 13,"respectively. .The cores B,

B, and 13 ca respectively, the insulatedcontacts E, and E. These contactsen ag withcontacts I J, I J, I J, and I The weights of the above-mentioned insulated contacts can be varied, and the distance of the pull of the cores' can be varied. On the up er end of the core B' there is attached the insulated contact F,

Specification of Letters Patent. v Application filed December 7, 1966. serial No. 346,748.

line M to the line P, P, and

raumeaa ril 16,1907.

which engages with the spring or flexible contact G.

H, H, H, and H- are leads connectin respectively, one side of magnet-windings C, C, and O to line K. L L L are leads connecting to the other side of the respective windings C, C, and O toline LL. Lead L connects line M to the other side of winding 0, that" is connected byline H, pre viously mentioned. Lead Q connects line M tothe insulated contact F.

side of the respective windings D, D, and D to th D, D, and D being respectively connected to contacts I, I, and I. l i

P, P, P, an P are leads connecting the different sections of resistance R to the respective contacts J, J, J, and J, the windl 5 O, O, and O" are leads connecting one edead N, the other side of the windings ings D, D, and D- being com leted from the through the res ective contacts I E J, I. E J, and I 'J. Lead -P is connected to contact J and one end ofthe resistance R. Line N is connected to the contact I and to the line P through the contacts I E J Sis a magnet-core energized by the'winding T, which is in series-with the motor.

Lead U connects one side of winding T to-one side of the line throu h switchC C. Line V connects other side 0 winding T to one side of the motor. Lead W is connected to other side of aforesaid switchC G and is connected; I

to lead N and one side of-the resistance R. Lead D D is connected to the other side of the aforesaid mentioned resistance R and to the opposite side of the motorthan line V is connectedto.

A A is an armattached tothe magnet-core 'S and carries ."afi insulated terminal Z; Theterminal Z carries the spring-contact B, B,

which enga es with the .contact Y.- Lead K is connecte to the line D D or the sam'e side of the motor that D D connects to. Line M is connected to terminal Y. Line X connects to the terminal Zand to the same side of motor as'lineV connects to.

The terminals Z and Y engageeachother through the spring-contact B B. The windingD is wound so as to produce the samedirection of magneto-motive force as C, D the same as C, and D the same as (3%.

The ma et-windin T is in series with the motor, a so the win lngs D, D, and D when.

their respective sections of resistance is out in the line, the windings D, D, and D function being merely to assist the windin 's C, C, and C and not strong enough to ho (1 their respective cores ,up. The magnet-winding T is so designed that a predetermined amount of overload current will raise the plunger or core S sufficiently high to open the contact B B on Y, which will open the magnet-circuit M K. Theinductive spark, at B B will be blown out, due to the-magnetic flux of the core S. .Upon the lifting of the core 13 the contact G upon F will be broken," which will open the circuit upon magnetwindings O, C

and G.' This inductive spark will also be blown out, due to the magnetic flux from the Q cent. of number of voltage has been applied.

. core B when, say, eighty per cent. of the I M K will per cent. of the line voltage, or depending on core 33'. The weighted contacts E, EQE, and E are all of different weights. It is obvious then that the amount of magnetism that'is just: required to pick up the core 0 will not pick up core 0 and that amount which is just required to pick up 0 will not pick up core '0, & c. The same effect can be produced by varying the ampere-turns of the windings C, G, (3, and C or by varying the 5 distance of the travel ofthe plunger, thereby increasingfheir gap. The'voltage of the line e from zero to nearly o-nehundred the amount of resistance cut out of the cir- 'cuitand the back-electromotive force of m o -.tor A. The windings. O, C, C", and C are,

each of high-enough resistance to safely be connected across the line voltage; but magnet-winding C is so designed to pick up core B when, say, ten per cent. of number of vol- .tagexhas been applied; magnet-winding C, designed to pick up B"? when, say, forty per Magnet winding C so, designed to pick up core B when, say, sixty-five per cent. of

number of voltage has been applied, and

magnet-winding O is so designed to pick up number of voltage has been applied: y The method of operation is thus: Suppose that the switch GC is closed, thereby supplye ing power'to the "circuit, current will then ance is oneehalf ohm.

there will bea drop in voltage of fifteen volts on the motor A, due to the ohmic resistance ,1-

which will cause the aforesaid voltage of-fifflow to. line U, magnet-winding T le ad V,-

through motor A,"-.lead D 1),-resistance R, lead W, andout on opposite side of line. It

will be assumed that; the full-load current of the mctor Ais thirty amperes and its resist; it is obvious than that teen to exist in the line M.K. This voltage 'will -be sufiioient to cause enough current to core B, thereby closing contact shuntingrpar't ofthe resistance R. This will immediately cause a greater amount of c'u r-' )renhtbflowand also Increase thevoltage of flow through magnet-winding C to up its -J- and the-IlinejMfK, Thisincrease in voltage will divide their current and merely assist respective windings (l, O, and U.- When the electromotive force will have increased to such an extent as to c ause enough current in magnet-winding C to pick up core 13, the following results will take place: The contacts 1 E J 'will be closed, thercbyshunting' the last section of resistance, which Y will mean all of the resistance cut out of theline.

The contacts G and F will disengage, causing the circuit of magnetic windings- (l, C, and

C to open and allowthe cores B, B, and B to return to the normal starting position. The ma net winding C will have the full potentia of motor A and will hold up, and the circuit'will be follows: Lead-U,magnet-winding T, lead V, motor A, lead D 1),

lead-1, contacts J E I, lead N, lead 95 W, and out on the opposite side of the line, the aforesaid movements thus accomplishing the first aforesaid objects of our invention.

In case the load on the motor was sufficient. to cause'a detrimental amount of current to startin the same as aforesaid first object.

I00 flow upon starting, the circuit would be upon The V0 tage of line M K would be that'which I is caused by the ohmic drop of the motor A, 'as previously stated, which would be sulh-.. cient to cause enough current to flow in magnet 'winding C to' pick up core B, thereby closingzcontacts I: E J and cutting-out or shunting that ,"section of resistancaIwhich e111 immediately cause an increased amount. of current and increasedamount of voltage f along the line M K. It the load on'the motor A isexcessive, it will not respond in the inann'er of starting. The. stated increased voltage of the line-M K, due to the ohmic re sistance ofthe-motor and the increased current, will not be sufficient to operate winding C and its corresponding parts." Therefore the amount of currentis limited to that which is'allowed toflow after the first'sectionof re sistance is cut out and the motor will'atta'ifn the corresponding tor ue, due to that amount of current'so long as t e load on the motor-is excessive enough to not allow it to,start,-

thereby accomplishing the aforesaid second,

object of our invention. Assuming that the motoris running under load and .a sudden overload is apphedfthe said overload. bein .sufiicient to cause aEdet -"Y riinental amount 0 current to flow, the'wind a predetermined amount will cause the core S to raise, thereby causing the contacts B B and Y to disengage, causing the circuit on winding C to open, which will allow the core 13 to drop to its normal or startin position, which immediately inserts in al the resistance R, which reduces the current to a safe amount. This reduction of the current will not be sufficient to hold up the core S so as to kee contacts BB and Y disengaged, butwill a low it to drop to its normal position, thereby closing the contacts B B and Y and causing a small voltage to exist in the line M K, due to the ohmic resistance of the motor A, which will cause enou h current to flow in energized by the aforesaid. varia le-voltage.

- ma et carr ing the means-to open the afore- -sa1 variab evolta e distribution circuit magnet-winding C to pic up the core B.

If the load has beendecreased to a safe amount,

the magnets will operate, as are hereinbeforedescribed first mentioned object If the aforesaid overload is still existing on the motor, the magnets'will operate as described in our hereinbefore second object, thereby accomplishing the third hereinbefore-mentioned object of our invention.

The following-described apparatus issuit ably mounted on an appropriate panel, and upon its being properly .roportioned' and connected throughout inc uding the switch indicated on thedrawing, all of which will be readily understood by those skilled in the art to which this invention relates.

Having thus described the nature and ob jectsof our said invention, whatwe claim as 1. Inthe combination of an electric motor and starting resistance, leads connected to the positive and negative side of the said elec* tric motor. said leads forming a variable-vole circuit, electromagnets' each with vari- Ie weight -cores, said electroma nets being new, and desire to secure by Letters Patent,

distr bution-circuit, and electromagnet' having its windings in series with aforesaid electricrnotor, the core of the aforesaid electrou on a predetermine movement of said core, all substantially as and for the purpose shown and described.

, 2.- In a startingpanel of the character described in combination with an electric .mo-

' tor and a-startingresistance, leads connected to-the positive and negative side of the said electric motor, said leads forming avariabla voltage circuit, an electromagnet havingits "winding in series with the. aforesaid. electric" motor, the core of the aforesaid-electromagnet carrying'means to open the aforesaid variable-Volta e distribution-circuit 'u on a predetermine .movement of said core, e ectromagnets each having a shunt. and series winding, said each shunt-wmd1ng connected net carryin across the aforesaid variable-voltage distributionecircuit, said series winding being connected in shunt to a respective section of the aforesaid resistance through contacts, said contacts engaging upon. the movement of the respective cores, all substantially as and for the purpose shown and described,

3. In a startmg-panel of the character described in combination with an electric mo torandits starting resistance, leads connected to .the. ositive and negative side of the aforesaid e ectric motor, sald leads forming a variable-voltage circuit, an electrorna et havin its winding inseries With the al o iesaid e ectric motor, the core of the aforesaid electromagnet carryin means to open the aforesaid variable-voItage distribution-circuit upon a predetermined movement of said core, an electromagnet having a shunt-Winding' and electromagnets having each a shunt and series winding, said each shunt-winding being connected across the variable-voltage distrlbution-circult, said each series windin of the magnets having each a shunt an series winding being connected in shunt to a respective section of the aforesaid resistance through contacts, said contacts engaging u onthe movement of the respective cores,

a substantially as and for the purpose shown I and described. 4. In a starting-panel of the character described,incombination with an electric m0- tor and a starting resistance, leads connected to the positive and negative side of said electric motor, said leads forming a variablevo'ltage circuit, an electromagnet having its winding in series with the aforesaid electric motor, the core of the'aforesaid electromagmeans to open the aforesald variable-vo tage distribution-circuit upon a predetermined movement of -said core, electromagnets each having a shunt-winding, said shunt-winding being energized from the shunt-magnets carrying means to open the aforesaid "shunt-windings, with the exception of its own, said openin' I of the shuntaforesaid variable-voltage distribution-cir- 'cuit, one of the said cores of the aforesaid windings taking place 11 on t e movement of a said core, all substantially as and for the purpose shown anddcscribed.

5. In a starting-panel of the character described the combination of an electric Inotor and starting resistance, leads connected to positive and ne ativeside of said electric motor, said'leads f circuit, a combination "of electromagnets orming a variablervoltage having a shunt-winding, and electromagnets I havin each ashnnt and series-winding,- said each s unt-wmding being connected acrossthe aforesaid variable-voltage distribution- .circnit, said -"-\electromagnetseach" basing- -variablewei h tcores, said cores of theelectromagnets aving each a shunt and s ri Winding eachml'fying means for short-oincuiting a portion of the aforesaid resistance,

through each of the abovementioned series windings and suitable contacts, the core of the aforesaid shunt-winding magnet carrying means to short-circuit its respective section of resistance upon its movement through suitable contacts, and carry means to ope n each. of the shunt-windings, "on each of the aforesaid magnets, :having each a shunt and series winding, all substantially as and for the purpose showmand-described.

6. In a starting-panel of-the character-de-- scribed in combination with-an electric "motor and starting resistance, leads connected to positive and negative side ofz-said 1 electric motor, said leadsrformingza variablewolt'age circuit, electromagnetisshavi each a-shunt- I winding, said each-shunt-win ing beingconnected across :the z-aforesaid-variable voltage distribution-circuit, said'electromagnets each having varialble-weightcores, said cores cars 7 rging means forrshortscircuitingea:portion of said'electric motorpthecore ofathe aforesaidelectromagnet carrying smeans .'.to open :the

e aforesaid resistance through suitable contacts upon :a :movement :of each of the aforesaidcores, one ofthe said: cores-carrying :means to opiemthe aforesaid shunt-windings with 'ftlle. exception \of its 1 own, :said opening of ithejs'hunt-windings itaking: lace on the movement of isaidcore, .an -e ectroma net having its Winding in series with the a' oreaforesaid variable-voltage =-distribution-"circuit upfon. aipredetermined 'movement of saidtage circuit, a combination'o ielectromagnets '7. wIn a-Qstairtingipanel{of.the character described with ia" combination of-anelectrimmo- .torand:aastartingiresistance:leads-connected to the positive-jandme tivezside of saidielectrio motor, saidzle'a-d'sz ormin a variablesvolhaving'laf shuntawindingr and electromagnets f having eachaa-shunt and-series winding, said '45 .,-the. aforesaid varia 1e avo tage distributiorieach shunt-windi be connected across circuit, said electromagnetszeach having variable-wei htcores, saidico'res ofithe eleotrm magnets J aving each =..a -shunt and vseries Winding, a each carrying ameans lforj short+circuiting a sectionof the "flfOIBSllld zre'sistance througheaclr of the aforesaidimentioned serieszwindings 'and suitableacontacts, ithe core of. the aforesaid shuntswindingimagnetcarry: 5

' "\tion of resistance 'npQni-its .movement', 'thr0ugh=.-suitable contacts, and carry means *in'gmeans to short+circui ti its f respective. secto open each of. the shuntawi ndingsoneachof :the af resaid'm-agnetshaving each'aishunt and-series windingmn electromagnet having its windings ir'rserieswith: the. aforesaid electric motor; the core of the aforesaid electro- 1 magnet carryingsmeans to opentheaferesaid "ivariable-voltage distribution-circuit upon a predetermined :rnovement of said core, all

core, all substantially :as and .fOI' theipurpcse is'hown'aml described.

magnets provided with electrical and me-' ehanical means to cause the said cores toops 'erate singly and consecutively as the voltage .is increased from zero to one hundred per cent; of the voltage of thewariable-voltage distribution-circuit, the windings of-the aforesaid ele'ctroma nets eonnected across the aforesaid varia le-voltage distribution-cir- -cuit each core carrying means for short-circuiting a-respective section of the aforesaid resistance through suitable contacts, upon the movement of each of the aforesaid cores,

one of the said cores carrying means to open the aforesaid magnet-windings connected across the variable-voltage distributiomcir- :cuit, with the-exception of its own winding,

said opening of the magnetwindin s takin' a place upon the movement ofthe sai core, al

substantially as and for the purpose shown and described.

9, The;combinationwithzazlnotor having an armature, of a-res1stanoe, su' ply-mains;

and aicontrollerfor .cntting,out;t e said resistance step by step comprising -,a series of ,electromagnets one ofathe saidnmagnets' haviinga 1 shnntewi-nding, the =remain each a. shunt land series Winding, said series erhaving winding being connected inshunt to. a respective section of .the aforesaid lresistance upon the operation of..the. core of the said magnets having each a shunt and series winding;

through contacts, said sl nnt windings being connected across a circuit, the said circuitvbe ing in parallel-With the said armature,- an elecatromagnetchaving :itsminding in series with *the. aforesaid motor, the core. of the aforesaid electroinagnet provided with =means-t'v open i the-aforesaid circuit vwhieh is inpa'rallelz-with ;the armature upon: a predeterminedmove.-

\ ment of; said core, allsubstantiallyas and for 4 thepurp ose shown anddescribed.

; :10. The'combination with aimotor-having an .-.'armat u re, of a. -'resistance', supply-mains and .a controller :for' -.cutting out said resistance step by step; comprising, a series ofi electromagnets, ione of1the-said electromagnets having a shunt-winding the .-remainder' having-each a-shuntandseries. windin saidse- -ries winding being connectedin s unt toga respective section of the aforesaid resistance upon the operation of the'core of the said circuit in parallel with thearmature upon a magnets having each a shunt and series Windpredetermined movement of said core, all 15 ingthroughcontacts,sa1dshi1nt-Windingsbesubstantially as and for the purpose shown .ing connected across a circuit, the said circuit and described. bemi in parallel with the said armature, one In testimony whereof We have signed our ception of its own,'upon a predetermined of t e aforesaid eleotromagnets hav ng a respective names to this specification in the core, said core provided with means to open presence of two subscribing witnesses.

the aforesaid shunt-wound coils, with the ex- DAVID R KNAPP movement of said core, an electromagnet hav- HOWARD D ing its winding in series with the aforesaid Witnesses: motor, the core of the said eleotromagnet -ALFRED B. BOTFIELD, provided with means to open the aforesaid HERBERT M. WALTER. 

